/*
 * SPDX-License-Identifier: Apache-2.0
 *
 * The OpenSearch Contributors require contributions made to
 * this file be licensed under the Apache-2.0 license or a
 * compatible open source license.
 */

/*
 * Licensed to Elasticsearch under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch licenses this file to you under
 * the Apache License, Version 2.0 (the "License"); you may
 * not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

/*
 * Modifications Copyright OpenSearch Contributors. See
 * GitHub history for details.
 */

package org.opensearch.action.admin.indices.stats;

import org.opensearch.common.io.stream.StreamInput;
import org.opensearch.common.io.stream.StreamOutput;
import org.opensearch.common.io.stream.Writeable;
import org.opensearch.index.shard.ShardId;

import java.io.IOException;
import java.util.Arrays;
import java.util.Iterator;

/**
 * IndexShardStats for OpenSearch
 *
 * @opensearch.internal
 */
public class IndexShardStats implements Iterable<ShardStats>, Writeable {

    private final ShardId shardId;

    private final ShardStats[] shards;

    public IndexShardStats(StreamInput in) throws IOException {
        shardId = new ShardId(in);
        shards = in.readArray(ShardStats::new, ShardStats[]::new);
    }

    public IndexShardStats(ShardId shardId, ShardStats[] shards) {
        this.shardId = shardId;
        this.shards = shards;
    }

    public ShardId getShardId() {
        return this.shardId;
    }

    public ShardStats[] getShards() {
        return shards;
    }

    public ShardStats getAt(int position) {
        return shards[position];
    }

    @Override
    public Iterator<ShardStats> iterator() {
        return Arrays.stream(shards).iterator();
    }

    private CommonStats total = null;

    public CommonStats getTotal() {
        if (total != null) {
            return total;
        }
        CommonStats stats = new CommonStats();
        for (ShardStats shard : shards) {
            stats.add(shard.getStats());
        }
        total = stats;
        return stats;
    }

    private CommonStats primary = null;

    public CommonStats getPrimary() {
        if (primary != null) {
            return primary;
        }
        CommonStats stats = new CommonStats();
        for (ShardStats shard : shards) {
            if (shard.getShardRouting().primary()) {
                stats.add(shard.getStats());
            }
        }
        primary = stats;
        return stats;
    }

    @Override
    public void writeTo(StreamOutput out) throws IOException {
        shardId.writeTo(out);
        out.writeArray(shards);
    }
}
